21 June 2010
ByAppeared in BioNews 563
The study, published in the journal Nature, compared the genetic makeup of 923 individuals with common autoimmune disorders to a control group of 648 individuals without them. They found a genetic mutation that interferes with the sialic acid acetylesterase (SIAE) enzyme in 24 of the group with autoimmune disease, but only two of the control group.
SIAE regulates the activity of the immune system's antibody-producing B cells. If SIAE control of the B cells breaks down, they may attack the body's healthy cells by mistake.
The study senior author Dr Pillai explained that the gene variant accounts for only about two or three per cent of autoimmune disease cases, but added: 'we are actively investigating other genes in this pathway that may be defective in a larger percentage of patients'.
Dr Pillai also noted there is further to go. Whether changes in the enzyme are all that is necessary to trigger autoimmune disease 'or if there are more things, we don't know,' Pillai said, adding: 'I suspect more things. I suspect it's not enough.'